Improving README.md docs

README.md

@@ -5,3 +5,142 @@ The official elastic.io library for bootstrapping and executing for connectors b
 To build the project run in terminal
 
     ./gradlew build
+
+> The official elastic.io library for bootstrapping and executing for Java connectors.
+
+[Maven Repository](https://mvnrepository.com/artifact/io.elastic/sailor-jvm)
+
+`sailor-jvm` is a **required dependency for all components build for [elastic.io platform](http://www.elastic.io) in Java**. Add the dependency in the `build.gradle` file in the following way:
+
+```groovy
+    compile "io.elastic:sailor-jvm:2.1.1"
+```
+
+## Building components in Java
+
+If you plan to build a component for [elastic.io platform](http://www.elastic.io) in Java then you can visit our dedicated documentation page which describes [building a component in Java
+](https://docs.elastic.io/guides/building-java-component.html).
+
+### Before you start
+
+Before you can deploy any code into our system **you must be a registered elastic.io platform user**. Please see our home page at [http://www.elastic.io](http://www.elastic.io) to learn how.
+
+> Any attempt to deploy a code into our platform without a registration would fail.
+
+After the registration and opening of the account you must **[upload your SSH Key](https://support.elastic.io/support/solutions/articles/14000038794-manage-your-ssh-keys)** into our platform.
+
+> If you fail to upload you SSH Key you will get **permission denied** error during the deployment.
+
+### Getting Started
+
+After registration and uploading of your SSH Key you can proceed to deploy it into our system. At this stage we suggest you to:
+*   [Create a team](https://docs.elastic.io/guides/teams-and-repos.html#creating-a-developer-team) to work on your new component. This is not required but will be automatically created using random naming by our system so we suggest you name your team accordingly.
+*   [Create a repository](https://docs.elastic.io/guides/teams-and-repos.html#create-a-component-repository) inside the team to deploy your new component code.
+
+### Examples of Java components
+
+Here is a list of components build on Java:
+
+*   [petstore-component-java](https://github.com/elasticio/petstore-component-java) to build your first component
+*   [salesforce-component-java](https://github.com/elasticio/salesforce-component-java) to connect to Salesforce API
+
+## Sailor logging
+
+Sailor uses [SLF4J](https://www.slf4j.org/manual.html) logging framework. 
+
+Supported log levels are:
+
+- `FATAL`
+- `ERROR`
+- `WARN`
+- `INFO`
+- `DEBUG`
+- `TRACE`
+
+Default log level is `INFO`. You can change default log level with environment variable `LOG_LEVEL`.
+
+Sailor logger adds the following extra context to log messages:
+
+- `ELASTICIO_API_USERNAME`
+- `ELASTICIO_COMP_ID`
+- `ELASTICIO_COMP_NAME`
+- `ELASTICIO_CONTAINER_ID`
+- `ELASTICIO_CONTRACT_ID`
+- `ELASTICIO_EXEC_ID`
+- `ELASTICIO_EXEC_TYPE`
+- `ELASTICIO_EXECUTION_RESULT_ID`
+- `ELASTICIO_FLOW_ID`
+- `ELASTICIO_FLOW_VERSION`
+- `ELASTICIO_FUNCTION`
+- `ELASTICIO_STEP_ID`
+- `ELASTICIO_TASK_USER_EMAIL`
+- `ELASTICIO_TENANT_ID`
+- `ELASTICIO_USER_ID`
+- `ELASTICIO_WORKSPACE_ID`
+
+## Component logging
+
+Sailor contains org.slf4j.Logger to make logs.
+
+Component logger usage example:
+
+```Java
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class ActionClass {
+
+  private static final Logger LOGGER = LoggerFactory.getLogger(ActionClass.class);
+
+    void someMethod() {
+        LOGGER.fatal('message');
+        LOGGER.error('message');
+        LOGGER.warn('message');
+        LOGGER.info('message');
+        LOGGER.debug('message');
+        LOGGER.trace('message');
+    }
+}
+```
+
+## Using http-reply emit
+
+This functionality is using to send http response for request made to 
+previous [webhook trigger](https://docs.elastic.io/getting-started/webhooks-flow.html) flow step.
+More information about HTTP reply [here](https://support.elastic.io/support/solutions/articles/14000052551-http-reply-enabling-the-two-way-messaging-conversation-through-request-reply-pattern). 
+
+Using component as request-reply step requires to add to component.json root:
+
+```
+    "service": "request-reply"
+```
+
+Also requires specifying of `X-EIO-Routing-Key` header which must contain request-reply key.
+Service need `Content-Type` to resolve output structure.
+
+Example of request-reply usage:
+
+```Java
+import io.elastic.api.ExecutionParameters;
+import io.elastic.api.HttpReply;
+
+public class ActionClass {
+
+  private static final Logger logger = LoggerFactory.getLogger(ActionClass.class);
+
+  public void execute(final ExecutionParameters parameters) {
+      final JsonObject headers = parameters.getMessage().getHeaders();
+      ...
+
+      logger.info("Emitting httpReply...");
+      parameters
+          .getEventEmitter()
+          .emitHttpReply(new HttpReply.Builder()
+              .status(200)
+              .header("X-EIO-Routing-Key", headers.getString("reply_to"))
+              .header("Content-Type", "text/xml")
+              .content(new ByteArrayInputStream(dataString))
+              .build());
+  }
+}
+```